ABSTRACT
Background: Patients requiring extracorporeal membrane oxygenation (ECMO) frequently necessitate tracheostomy due to prolonged mechanical ventilation. SARS-CoV-2 infection has been associated with different coagulation disorders and may increase the risk of bleeding in high risk patients such as those requiring ECMO. Here, we aim to determine if SARS-CoV-2 increases the risk of bleeding after tracheostomy in ECMO patients. Methods: A retrospective review of all patients requiring ECMO at our institution between March 20 of 2020 and December 31 of 2021 was conducted. Patients requiring tracheostomy after ECMO were included. Demographics, COVID-19 status, tracheostomy approach and post-procedure bleeding events were collected. Statistical analysis was performed using student T-test for nominal variables and Chi-Square test for categorical variables. Results: A total of 267 patients required ECMO during the defined study period. Of these, 112 patients had tracheostomy placement and were included for analysis. Seventy-five percent (84/112) of tracheostomies were done percutaneously and 25% (28/112) were done using surgical open technique. Mean age was 46.2 years ±14.3, 68% were male, mean BMI was 29.9Kg/m2 ±5.5. Seventy patients (63%) had COVID-19. The remaining 42 (37%) required ECMO due to polytrauma, cardiogenic shock, and respiratory failure after other operations such as heart and lung transplant. Of the 112 tracheostomies performed, 34% (38/112) had severe bleeding after tracheostomy placement requiring blood transfusion or additional interventions to control the bleeding. Of the 70 patients with COVID-19, 47% had severe bleeding compared to 12% in the non-COVID-19 group (p=<0.001) (Table). Conclusion: The rate of severe bleeding after tracheostomy was significantly higher in patients with COVID-19 compared with those that did not have SARS-CoV-2 infection. COVID-19 status should be considered before tracheostomy in ECMO patients as it may increase the risk of bleeding complications (Table Presented).
ABSTRACT
This paper study suggests the specifications for high-efficiency, short-haul utility aircraft. This class of aircraft is used extensively in the multinational express package delivery service. Concurrent with the COVID 19 pandemic upending passenger travel, there has been a broad increase in the demand for air cargo. We forecast a need for more efficient short and medium range aircraft that offer route time savings and lower operating costs. Using current market planes designed with similar mission requirements, payloads, and engines – a general plane was created and optimized around the operating model of the present-day FedEx package delivery feeder fleet. The modification and optimization process was completed using a Model-Based-Systems-Engineering (MBSE) approach utilizing Phoenix Integration’s ModelCenter, Excel, MATLAB, and SOLIDWORKS. The final design achieved 40% improvement in fuel efficiency over the current fleet, and improvements in speed, payload, and range while in compliance with FAA regulations as a class E cargo aircraft certified under 14 CFR Part 25. © 2022, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.